apparentredistributionof activity into zones of ischemia ina matter of 3—4hr (7).

Althoughzonesof persistentdecreasedperfusionwereinitially thought to representscar, recent studiesdemonstrated viable myocardium in up to 50% of these regions.Improved myocardial perfusion and function after revascularization and persistent metabolic activity have beendescribed in myocardial segments that have been characterized as nonviable on the basisof a “persistentdefect―(8—11).This suggested that redistribution of @°‘Tlmay beprolonged in severely compromised but viable myocardium and that @°‘Tlimaging could be improved in somecasesby re-imagingas long as 24 hr later (12). An alternative approach is reinjection of @°‘Tland a third set ofimaging data immediately after acquiring the redistributiondata(13,14). Reinjectionoffersa practicalconvenientalternative to 24-hr imaging (15, 16) and has been shown to bemore accurate for determining viability than the standard4-hr redistribution method (13—19).

The relative myocardial concentration of 201'flafter reinjection reflects a combination of the @°‘Tlkinetics ofuptakeduringstress,subsequentclearanceanduptakefollowing rest reinjection. The purposeof this study was tocharacterizethe reinjected201'flimage.In particular,thepossible influence of the following variables were assessed:gender, stress type (exercise or dipyridamole), exerciselevel, initial @°‘Tldose, time interval between the two injections, interpretation of the @°‘Tlstress test and extentand character of segmental abnormalities.

METhODS

Patient PopulationGroup1. Stress-reinjectionthalliumdatawereevaluatedon 204

consecutive patients (average age 62 yr. 128male, 76 female) whohadbeen referredfor eitherexercise(n = 160)or dipyridamole(n= 44) 201'fl studies. Group 2. An additional 63 patients (mean age

62 yr. 40 male, 23 female, 58 exercise, 5 dipyridamole) had standard redistribution data collected immediately prior to reinjection.This group was analyzed only to assess the possible impact of20111 myocardial washout during redistribution on myocardial ac

tivity afterreinjection.Clinical information regardingthe patients was derived from

interviews and physical examinations by the cardiologists performingthe stress tests. ainkal indicationswere typical chest

The @°@T1imageafterreinjectionwas characterizedbyanalysisof stressand reinjectiondataacquiredin 204consecutivepatients undergoing planar @°@T1cardiac stress tests. In an addilional63 patients,redistributiondatawerealsoacquiredto determinethe effectof washouton the final reinjectionimage.Maximumcountdensitiesfor the myocardium,lungand liverweremeasured,andthe ratiosbetweenthestressandredistributionandthe stressand reinjectionsetsof datawerecalcuIated.In patientswfth <5% proba@y of coronaryaitery disease(CAD)(“normal―group),the reinjectionimagewas typifiedbylessmyocardialactivity(initial/reinjection= 1.22),slightlylesslungactivity(initial/reinjection= 1.05)andgreaterhepaticactivitycomparedto theinitialpostexerciseimage.Inmalepatientsw@i>5% probabilityof CAD,peakmyocardialactivityafterreinjectionwasaffectedbythefollowingvadables:theintervalbetweenstressand reinjection,the amountofthe initialdoseand the @°@T1scan results (normal201@flstudy: initial/reinjection= 1.16;abnormal = 1.06; p < 0.009). MyocardieiactMty after reinjectionwaslinearlyrelatedto myocardialactivityafter redistribution(r =0.82).Therewas no significantinfluenceby thosevariablesinthe76womenwhowerestudied.Inconduston,myocardial@°i1was decreased after reinjection in normal patients.The resultsindicatethatthereisanincreasedlikelihoodofunderlyingCADinmale patientsundergoingexercisestresstests when @°@T1myocardialactivityon reinjectionis greaterthanonthe initialimage.

J NucI Med 1993; 34:879-884

hallium-201 myocardial imaging has become a mainstay in detection and management of coronary artery disease (CAD) (1—4).Originally, the technique for 201'flmyocardial imagingwas performed on two separatedays, onefor injection during stress and another for reinjection at rest(5,6). The technique was simplified to a single injectionwhen it was recognized that the kinetics of @°‘Tlresulted in

ReceivedFeb.6, 1992;revisionacceçledFeb.25,1993.Forcorrespondenceor reprintscont@ Kennethk Mckualck,MD,DMS@nof

Nudear Methane, Mass@husetts General Hospital, 55 Fruit St, Boston MA,02114.

*Curraltaddress:DMsionofCardkilogy,M.BufaliniHospital,Cessna,Italy.tCurrentaddress:35EthanikisAnilnis,P@@agou,Greece.@Currentaddress:PharmeceuticalResearchInstitute,BristolMyersSquibb,

Princeton,NJ.

879TheReinjectionThalliumImage•Pienetal.

Characterization of the Reinjection ThalliumImagePierluigi Pieri,* Kenneth A. McKusick, Alan J. Fischman, Nathaniel Alpert, Constantinos Bougast andH. William Strauss@

DivLiionofNuclear Medicine, Department ofRadiologj@,Massachusetts GeneralHospital@Boston, Massachusetts andDepartment ofRadiology, Haivard Medical Schoo4 Boston, Massachusetts

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pain (n = 39),atypicalchestpain (n = 47),“ruleout CAD―(n = 55), riskstratificationaftermyocardialinfarction(n = 52) andassessmentofmyocardialperfusionafterpercutaneoustransluminal angioplasty(n = 11).Thirteenofthe 204 patientshadless than5% likelihood for coronary heart disease on the basis of thecriteria established by Diamond and Forrester (20). These 13subjects, who also had normal thallium studies, comprised a “normal―comparisongroup.

Stress TestsPatientsfastedat least4 hr priorto thestresstest.Betablock

ers were withheld for the previous 48 hr whenever clinicallyfeasibleandtheophyllinecontainingmedicationsandcaffeinewere withheld prior to dipyridamole stress tests. Theexercise study was performed on a treadmill using a Bruce protocol. Exercise was terminated at the predicted maximal heartrate (PMHR), or because of symptoms, clinical signs, 4 mm orgreater horizontal ST depression in the absence of pain and hypotension, serious arrhytbmias or hypotension. Submaximal exercise was performed in patientswith recent myocardial infarctionor surgety. Twenty-two patients had low-level exercise (<50%PMHR),76 reachedmoderate-levelexercise(50%—85%PMHR)and 61 achieved high-level exercise (>85% PMHR). For the cxercise stress test, @°“flwas injected at peak exercise followed byan additional 30—60sec of exercise. For the dipyridamoletest,0.568 mg/kg were infused over 4 mm and @°‘11was injected 6 mmlater.Betweentheendof dipyridamoleinfusionand @°‘Tlinjection, three patients had low-leveland seven patients had moderate-levelexercise,while34didnotexercise.

Thalllum-201 DosesThe initial 20111dose was predicated upon body weight and

rangedfrom74to 110MBq(avg.96.5MBq);the second @°“fldosewas fixed at 37 MBq. Patients were encouraged to eat between thetwo injections.

ImagIngThree initial64 x 64 planarimages were acquiredfor a preset

timebasedonthetimeneededto acquirea400count/pixelmyocardial density on the initial anteriorview (average time 6 mm)usinga standardfieldofview camera(Technicare420,Solon,OH)equipped with an all-purpose, parallel-hole collimator adjusted toimagethe 80keV mercuryx-ray with a 20%window. Datawererecordedin a TechnicareM@S560computer.Afteran intervalof2.5—6.5hr (avg. 3 hr, 53 miii), patients were reinjected with asecond dose and about 15 min later, preset time images wererecorded for the same interval as the initial acquisition.

ECGandthalliumstresstestswerecharacterizedas“normal―or “abnormal―based upon the finalinterpretationof the cardiologists and nuclear medicine physiciansperforming the studies.Abnormalscanswerefurthercharacterizedforthepresenceandextent of “reversible―and/or“persistent―defects. If the conclusionswere not definite, the resultswere classified“uncertain.―

Data AnalysIsIn Group 1 (204patientswho had stress and reinjectiononly),

the maximumcount densities in the myocardium, lung and liverwere measured by one observer from the anteriorview on theinitial andreinjectedimages.Intraobservervariabilitywas lessthan 5% on measurementsrepeated five differenttimes in fourpatients. The followingratios of maximumcount densitieswerecalculated:myocardialuptakebetweeninitial and reinjectedimages (myo I-to-R); lung uptake between initial and reinjectedimages(lungI-to-R);initiallung-to-myocardialratio(lung-to-myo

I);reinjectedlung-to-myocardialratio(lung-to-myoR);initialliver-to-myocardium (liver-to-myo I); reinjected liver-to-myocardium (liver-to-myo R).

In Group2 (63patientswho alsohadredistributiondata),theratios myo I-to-R, lung-to-myoI and lung-to-myoR were calculatedbothfromthepeakmaximalactivityof theorganandfromthe count density in ROIs set over the most normal zone ofmyocardium,the left lowerlung field and the left lobe of the liver.The regions encompassed a minimum of 50 pixels. No signfficantdifferences were found in ratios calculated from peak maximalactivityand fromROl count density. In addition,in Group 2 theratio of myocardialactivitybetween the initialand conventionaldelayed“redistribution―images(myoI-to-D)was calculatedandrelated to myocardialactivityafter reinjection.

StatIStIcal AnalysisDataareexpressedasaverage±s.e.Weusedalinearstatistical

modeltotesttheinfluenceofthefollowingclassificationvariables:gender, stress type and probabilityof CAD. Possible influence ofinjected dose and the interval between injections were included ascovariates.Stresstypewaseitherexerciseor dipyridamole.Probability of CAD was veiy low (<5%), low (5%-24%), moderate(25%—75%)or high(>75%).All statisticalcalculationswere performed using SAS statistical software. Calculations using linearmodels (ANOVAs) were performed with the general linear modelprocedure.Duncan's multiplerange test was performedfor eachof the classificationvariables.

RESULTS

The reinjected image in the 13 patients with <5% likelihood of CAD (“normal―)was characterizedby lessmyocardialactivity, slightly lesslung activity andmuchgreaterhepatic activity in comparisonto the initial stress image(Table 1, Fig. 1). In general, the same patternwas found inpatientswith >5% likelihood ofCAD. Myo I-to-Rwas 1.22in normal patients, 1.10 in the subgroup of patients with>5% probability of CAD who had exercise @°‘Tlstudiesand 1.04 in those who received dipyridamole. However in35/147 (24%) exercise patients and in 17/44 (39%) dipyridamolepatients,myocardialactivitywas actuallygreaterafter reinjection in comparison to the initial images.

We therefore analyzed the myo I-to-R parameterto determine if it varied with sex, thaffium results and exercisetype, taking into account variations in thallium dose andtime between initial and second injections. A linear modelwas used to describe myo I-to-R in terms of the type ofstress and results of the thaffiumscan, with thaffiumdoseand time between injections included as covariates. Of 128men, 26 were given persantine and 102 had graded exercise. The overall F-value was 5.76 (df = 7,120, p = 0.0001).The ratio of peak myocardial activity between the initialand reinjected images (myo I-to-R) was greater in thosepatients who had exercise than those who had dipyridamolestresstests(1.10 ±0.01versus1.04±0.03) (F =5.12, p < 0.02; and by Duncan's multiple range test, p =0.05).

The effect of the 20111results on the myo I-to-R parameter was significant (F = 3.55, p = 0.009). A Duncan'smultiple range test indicated significant differences in myo

880 TheJournalofNuclearMedicine•Vol.34•No.6 •June1993

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A priorilikelihoodof coronatyarteiydisease<5%

Exerdse>5%Exerc@seD@yñdande(n= 13)(n = 147)(n = 44)

*p < 0.05, tp < 0.01 whencomparedto exerciseresultsinpatientswith>5% probabilItyof CAD.

$p< 0.05,‘p< 0.01whencomparedto dipyridamoleresults.Myol-to-R= myocardlaluptakebetweeninitialand reinjectedim

ages;LungI-to-A= lunguptakebetweeninitialandreinjectedImages;Lung-to-MyoI and Lungto MyoR = lung-to-myocardlalratiosIn theInitialand reinjectedImages;Uver-to-MyoI and Liverto Myo R = liverto-myocardiairatiosinthe initialandreinjectedimages.

I-to-R for thallium diagnoses of “normal―(mean myoIIR =1.16) versus abnormal studies with “persistent―(mean =1.05) and “reversible―(mean = 1.04) defects. There wasno significantdifference for myo hR for thalliumdiagnosesof “uncertain―and“fixedplus reversible―defects.A myoI-to-R < 1.0 was associated with a high incidence of abnormal @°‘Tlresults in maleswho exercised:28/35(80%)witha myo I-to-R < 1 had abnormalthalliumresults when comparedto 58/112 (52%)with myo I-to-R 1 (p < 0.01) (Fig.

INITIAL REINJECT

2). The 20111results were not a significant variable on myoI-to-R in the dipyridamole group nor in the 76 women whohadexercisestresstests.

There was a small but significantincrease in myo I-to-Rdirectly related to the interval betweenthe two injections(F = 8.22, df = 1, p = 0.005); that is, the greater theinterval between the two injections, the lower the myocardialactivity afterreinjection.Also, the amountof the initial20111 dose had a significant effect on myo I-to-R

(F = 11.6, df = 1, p = OMO1).The level of exercise did not show a signifIcanteffect

when analyzed by linear models.

RelationshIp Batween Myo 140-0 and Myo I-to-R InGroup 2

A linearrelationshipwas found between myo I-to-D andmyo I-to-R (r = 0.82), which suggests that myocardialactivity after reinjectionwas affected by the rate of myocardial washout and thus residual myocardial activity priorto reinjection (Fig. 3).

Lung-to.Myocardlum RatiosInitially increased @°‘Tllung uptake (lung-to-myo I

>0.55) is known to be evidence ofleft ventricular dysfunction and is a negative prognostic indicator in patients undergoingstress @°“fltests (21). The initial lung-to-myocardial ratio was higher in patients with >5% CAD than innormal patients (p < 0.001, Table 1) and in patients whohad abnormal20111results (0.51 ±0.01) when comparedtopatients with normal @°‘Tlresults (041 ±0.003). The relationship between lung-to-myo I and thallium results isshown in Table 2. Following reinjection, the mean lung-to

TABLE IRelativeLung,UveraridMyOcardialRatios

Myol-to-R1.22 ±O.03@1.10 ±0.01@1.04 ±0.03Lungl-to-R1.05±0.041.05±0.021.03±0.02Lung-to-Myo

I0.38 ±O.02@0.47 ±0.010.45±0.02Lung-to-MyoA0.45 ±0.020.49 ±0.01@0.45 ±0.01Liver-to-MyoI0.39 ±0.03*0.48 ±0.01'0.98 ±0.05Liver-to-MyoA0.83 ±0.050.88 ±0.010.86±0.02

ANT

LAO 45°

LAO 70°

FiGURE 1. Normal exerclse/reinjection @°ii@ in a patientwith<5% lIkelihoodofCAD (ImagesnotnOrmalized).ThereinjectedImageshaveslightlylessmyocardlalactivityandgreatersplanchnlcactivitycomparedto the initialImages.

ANT

LAO 45°

LAO 70°

FiGURE 2. Exami@eof abnormal exercise@@notnormalized).ThereisdiffuseincreaseinmyocardlalactMtylnthereinjected images, suggesting slow myocardial washout. This patienthad CADwith LADocclusion.

TheReinjectionThalliumImage•Piedatal. 881

INITIAL REINJECT

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Exerciselevel Uver-to-MyoI Liver-to-MyoA

*p< 0.05whencomparedtohIgt@level;tp < 0.01whencomparedtomoderatelevel@< o.ooi whencomparedto llver-to-myoI.

and (2) variable washout and redistribution over the nextseveral hours (7). With the same-day, dual-injection approach, reinjection imagesare related to the flow conditions present at stress and at rest as well as variable washout and redistribution between the two injections.Thallium-201 distribution immediately after reinjection reflects the residualactivity left from the stress injectionplusthe added @°‘Tldosegiven at rest for the reinjection images.

The results of this study indicate that the reinjection20111 image in normal patients (<5% likelihood CAD) is

characterizedby less myocardialactivity, slightly less pulmonaiy activity and greater hepatic activity than after cxercise. In all 13normal patients, myocardial activity waslower after reinjection. The initial dose was prescribed onthe basis of body weight. Patients were encouraged to eatbetween the initialandreinjectiondoses to accelerate myocardial 20111clearance before reinjection (22). It wasthought that the amount of the initial @°‘Tldose and theinterval between injections would affect the ratio of myocardialactivity betweenstressandreinjectionimagessincethe dose for reinjection was the same for all patients. Infact, those variables had only a small effect upon the initialreinjectionmyocardialratio. In this study, the variable thatmost affected this ratio was the outcome of @°@Tlimaging,with themostsignificantvariablebeingthepresenceorabsence of an abnormal @°‘Tlresult. In females, there wasno significant influence of initial @°‘Tldose, the intervalbetween injections or the @°‘Tlresults on myo hR. Thismay be consistent with previously described sex differences in myocardialwashout (23).

From a practical clinical perspective, the data suggestthat there is greater likelihood of underlying coronary arteiy disease in male patients undergoing exercise stresstests when there is greater @°‘Tlmyocardialactivity on thereinjection image than on the initial study.

To assess if the ratio of myocardialactivity between theinitial and reinjected images could reflect myocardial washout(24,25),wecorrelatedthatratio(myoIIR)with theratioof myocardial activity between the initial and the delayed“redistribution―images (myo l/D). A linear relationshipwas found between these parameters (r = 0.82), whichsuggests that the pattern of myocardial uptake in the reinjected image is affected by the rate of myocardialwashout(Fig. 3). This may imply that an indirect qualitative approach to myocardialwashout could be possiblewith the

No.01PatientsExercise

20111results(n=125)*Normal

AbnormalUncertainLung-to-Myo

I250 25(100%)0>0.55Lung-to-Myo

I403(7%) 34(85%)3(7%)0.5Lung-to-Myo

I8542(49%) 39(46%)4(5%)<0.5*On@y

patientswho had highor moderatelevelexercise.

TABLE 3Uver-to-MyocardialRatiosand Level of Exercise4.0

3.5

c@ 3.0

—32.5

@ 2.0

@1.5>-

@ 1.0

05

0.00.0

H@h0.42 ±0.020.84 ±0.02@Moderate0.50±0.02'0.89 ±0.02@Low0.57±O.O3@0.93 ±0.04@

0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

MYOCARDIALlID

FiGURE3. Effectof @@111redistnbutionon myocard@alactMtyafter ralnjection.There is a relationshipbetweenthe myocard@activitybetweenthe initialand conventional“redistribution―images(myolID)andthe ratioof myocardualactivitybetweenthe initialandthe reinjectedimages(myo l/R) (r = 0.82).Thus, it suggeststhatmyocardialactivityafterreinjectionisaffectedbythe rateofwashoutpriorto reinjection.

myocardial ratio was less than 0.5, even though the injections were performedat rest (Table 1).

Uver-to-Myocardlal RatioIn patients who exercised, there was greater hepatic

activity after reinjection than at stress. The average liverto-myocardialratios for all patientswith exerciseanddipyridamole @°‘Tlstress tests are shown in Table 1. Theeffect of exercise level on liver-to-myocardial ratios isshown in Table 3.

DISCUSSION

Thallium reinjection is superior to the single injectionapproachfor detecting myocardial ischemiaand viability(13—19).With the single injection approach, the images arerelated to two different phenomena: (1) initial organ perfusion as affected by exercise level or dipyridainole effect

TABLE 2RelationshipBetween Lung-to-MyoI and @°i1Resufts*

882 TheJournalofNuclearMediane•Vol.34•No.6 •June1993

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ratio myo hR. In patientswith <5% likelihood of CAD, themyo hR was >1 (1.22 ±0.03) and decreased with increasing probabilityof CAD (1.10 ±0.01 in patients with >5%probabilityof CAD andeven lower (1.06 ±0.02) in patientswith abnormal @°‘Tlresults). An abnormal‘@°@Tlstudy cccurred more frequently in patients in whom there washigher myocardial 201'flactivity after reinjection.

The differencebetween myocardialactivity afterreinjection versus stress was less in patients who had dipyridamole stress tests. This probably reflects the slowerwashout rate noted in dipyridamole @°‘Tlstudies(26).

Lung activity tended to decrease after reinjectionwhencompared to stress, but the differences were not signillcant. As previously reported, initial lung-to-heart ratioswere affected by CAD and the level of exercise effort(27—29).Increased initial lung uptake is evidence of leftventricular dysfunction and is a negative prognostic indicator (21). It is noteworthy that the reinjected lung-tomyocardial ratios were not increased, although the patientswere injected at rest.

It hasbeengenerallyrecognizedthat there is an inverserelationship between the level of exercise and hepatic @°@Tluptake. On the basis of these results, the predicted initialliver-to-heart ratio on exercise would be 037 (±0.03) at<50% PMHR, 0.5 (±0.02) at 50% PMHR and 0.42(±0.02)at 85% PMFIR (Table 3).

At our institution, the reinjection approach currentlyconsists of two injections of@°'Tlon the same day; the first,after stress, and the second three or more hours later.Patients are encouraged to eat after the initial images areacquired in order to maximize myocardial clearance. Forreinjection, a dose of 37 MBq @°‘Tlis given with the patientat rest; delayedimagesarerecordedbeginning15min later.Therefore, only two sets of images are collected: the initialand those acquired after reinjection. This method differsfrom the reinjection protocol described by Rocco and Dilsizian (13,14), which is performedwith the stress-redistribution-reinjectionapproachandthreesetsof images.It hasbeen noted that thallium reversibility may be underestimated if redistributiondataare not obtained. This has beenshown to occur in only a small number of myocardialregions (30). The reinjection approach performedwithoutconventional 3- to 4-hr redistribution imaging precludesanalysis of washout in thallium studies. Nonetheless, thisstudy indicates that higher myocardial activity after reinjection in comparison with the initial images can be anindirect estimation of slow myocardial washout.

REFERENCES1. Strauss HW, Harrison K, Langan JK, LebOWitZ E, Pitt B. Thaffiwn-201 for

myocardial imaging. Relation of thallium-201to regional myocardial perfusion.Circulation1975;51:641-645.

2. RitchieJL, TrobaughGB, HamiltonOW,et al. Myocardialimagingwiththallium-201at restandduringexercise.Comparisonwith coronaryarteriographyand restingand stress electrocardiography.Circulation197756:66—71.

3. RitchieJL, ZaretBL, StraussHW,etal.Myocardialimagingwiththaffium201:amulticenterstudyinpatientswithanginapectorisoracutemyocardialinfarction. Am I CanJiol 1978;42:M5-350.

4. RozanskiA, BermanDS,GrayR,Ctal.Useof thallium-201redistributionscintigraphyinthe preoperativedifferentiationofreversibleand non-reversibiemyocardialasynergy.Circidation1981;M:936-944.

5. LebowitzE,GreenMW,FairchildR,Ctal.Thallium-201formedicaluse.JNuciMed 1975;16:151—155.

6. BloodDK, McCarthyDM, SciaccaRR,Ctal.Comparisonof singledoseanddoubledoseofthalliummyocardialperfusionimagingto detectpatientswith singleand multivesseldisease.Clivulation197858:m-778.

7. PohostGM, Zir LM, MooreRH, McKusickKA, GuineyTE, BellerGA.Differentiationoftransiently iSChCmiCfrominfarctedmyocardiumby serialimagingafter a singledose of thallium-201.Circulation1977;55:294-302.

8 Gibsonas, WatsonDD, TaylorGi, et al. Prospectiveassessmentof regional myocardialperfusion before and after coronaiy revascularizationsurgeryby quantitativethallium-201scintigraphy.JAm CoilCardiol1983;1:804—815.

9. Liu P, Kiess MC, Okada RD. et al. The persistent defect on exercisethalliumimagingand its fate after myocardial revasculatization:does itrepresentscaror ischemia?AmHearti 1985;110:996-1001.

10.BnmkenRC,KottouS,NienaberCA,etal.PF1@detectionofviabletissuein myocardialsegmentswith persistentdefectsat @°‘11SPECF. RadioIo@1989;172:65-73.

11.TamakiN, YonekuraY, YamashitaK, et al. Relationof leftventricularperfusionandwail motionwith metabolicactivityin persistentdefectsonthallium-201tomographyin healedmyocardialinfarction.Am I Cardiol1988;62:201—@l8.

12.GutmanJ,BermanDS,FreemanM, etal.Tunetocompleteredisml,utionof thallium-201in exercisemyocardialscintigraphy:relationshipto thedegreeof coronaly arteiy stenosis.Am Hearti 1983;106:989-995.

13. Rocco 1, Dilsizian v, McKusick KA, Fischman AJ, Boucher CA, StraussHW. Comparisonofthalliumredistributionwith rest “reinjection―imagingforthedetectionofviablemyocardium.AmI Caidiol1990;66:158—163.

14.Dilsizianv, Roc@T, FreedmanNMT, LeonM, BonowR. Enhanceddetectionofischemicbut viablemyocardiumby the re-injectionof thalliumafter stress-redistributionimaging.N &vgllMed 1990,323:141-146.

15.DilsizianV, SmeltzerWR,FreedmanN?.ff,DextrasR, BonowRO.Thailium reinjection after stress-redistribution imaging. Does 24-hour delayedimagingafter reinjectionenhance detectionof viable myocardium?Circulation 1991;83:1247—1255.

16.KaydenDS,SigalSL, SouferR, MattersJ,ZaretBL, WackersFJ.Thailium-201 for assessment ofmyocardial viability quantitative comparison of24-hourredisthbutionimagingwith imagingafterreinjectionat rest.JAmCoilCardiol1991;18:1480-1486.

17.BonowRO,DilsizianV, CuocoloA, BacharachSL Identificationofviablemyocardiumin patientswith chroniccoronaiy arteiy diseaseand leftyentriculardysfunction:comparisonof thalliuni-201Scintigraphywith reinjectionandPETimagingwith‘8F-fluorodeoxyglucose.Circulation1991;83:26-37.

18.PieriPL, McKusickKA, TisselliA, AcitOP. StraussHW. Detectionofischemiaafter myocardialinfarction:comparisonof thallium-201re-injection vs redistribution in a high risk population (Abstractj. J Nuci Med199031:743.

19. Tamaki N, Ohtani H, Yonekura Y, et al. Significance offill-in after thallium

201reinjectionfollowingdelayedimaging:comparisonwithregionalwallmotionandangiographicfindings.J NuciMed199031:1617-1623.

20.DiamondGA,Forrester35.AnalysisofprObabilityasanaidintheclinicaldiagnosisofcomnaiy artety disease.NEngIJMed 1979;300:1350-1358.

21. GillJB,RuddyTD,NewellJB,FilkensteinDM,StraussHW,BoucherCA.Prognosticimponance of thalliumuptake by the lungsduringexercise incoronaiy arteiy disease.NEngIJMed 1987317:1485-1489.

2@WilsonRA, SullivanPF,OkadaRD,etaLTheeffectof eatingonthalliummyocardialimaging.Chest 1986;89:195-198.

23. Eisner RL, Tamas Mi, CloningerK, et al. Normal SPECT thallium-201bull's-eyedisplay:genderdifferences.JNucl Med 1988;29:1901-1909.

24.Maddahi3,GarciaEV,BermanDS,WaxmanA, SwanHJC,ForresterJ.Improvednoninivasiveassessmentof comnaiyarterydiseaseby quantitative analysis of regional stress myocardialdistribution and washout ofthallium-201.Circulation1981;64:924-935.

25.BatemanTM,MaddahiJ,GrayRi,etal.Diffuseslowwashoutofmyocardialthallium-201:a newscintigraphicindicatorofextensivecomnaiy arteiydisease.JAm CoilCaidiol 1984;1:55-64.

26.O'ByrneGT,RodriguesEA,MaddahiJ,etal.Comparisonof myocardialwashout rate of thallium-201betweenrest, dipyridamolewith and withoutaminophylline,and exercisestates in normalsubjects.AmI Canliol 1989;64:1022-1028.

27. BinghamJ,McKusickKA,StraussHW,BoucherCA,PohostG. Influence

883TheReinjectionThalliumImage•Pieriatal.

by on October 19, 2020. For personal use only. jnm.snmjournals.org Downloaded from

of coronary artei@vdisease on pulmonaiy uptake of thallium-201. Am JCaniid 1980;46:821—82&

28. Boucher CA, Zir LM, Belier GA, et al. Increased lung uptake of thallium201duringexercisemyocardialimaging:clinical,hemodynamicandangiographicimplicationsin patientswith coronaiy artery disease.AmJ Cwdiol1980;46:189-196.

29. BrownI(A, BoucherCA, Okada1W,StraussHW, PohostGM. Quantification of pulmonaiythallium-201activityafter uprlajd exercise in normalpersons: importanceof peak heart rate and propanololusage in definingnormalvalues.AmI Canliol 198453:1678-1682.

30. DilsizianV, BonowRO.Differentialuptakeandapparent @11washoutafter thallium reinjection. Circulation 1992;85:1032-1038.

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PURPOSEA 72-yr-oldmanwithmultipleskinandsoft-tissueulcerations underwent bone scintigraphy followed1wk later by labeled leukocyte imaging toinvestigate possible osteomyelitis. One yearearlier, the patient had received radiation therapytoarightapicallungcarcinoma.Thebonescan(Fig.1)demonstratedmultiplehealedleftposterolateral rib fractures and a remotecompression fracture ofthe first lumbar vertebra.Thewell demarcatedzone ofdecreaseduptakeinthe upper thoracic spine and posteromedial ribstypifies the postradiation scintigraphic pattern.Labeled leukocyte imaging (Fig. 2) showedprofound photopenia in the previously irradiatedtenitoly; the changes appeared much moreextensive as compared to the bone scan. Radiationtherapy resulted in a striking loss of functionalbone marrow in the thoracic spine and ribs.

RADIOTRACERTechnetium-99m-oxidronate(HDP), 18mCi;

@Tc-HMPAO-labeledautologous white bloodcells, 8.5 mCi.

ROUTE OF ADMINISTRATIONIntravenous (both tracers).

TIME AFTER INJECTIONFive hours for HDP and 3.5 hr for WBCs.

INSTRUMENTATIONSiemens Basicam gamma camera with general, allpurpose collimator (both scans).

CONTRIBUTORSE. Oates,D.M. Achong,J.L. Becker,N.L. Sheaand J.P. Norenberg.

INSTITUTIONNew EnglandMedicalCenterHospitals,Boston,Massachusetts.

FIGURE 1. Bone scan, posteriorthorax,5 hr postinjection.

FIGURE2.Technetium-99m-labeledWBCs,posteriorthorax,3.5 hrpostinjection.

884 The Journal of Nuclear Medicine•Vol. 34 •No. 6 •June 1993

FIRST IMPRESSIONS

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1993;34:879-884.J Nucl Med.   Pierluigi Pieri, Kenneth A. McKusick, Alan J. Fischman, Nathaniel Alpert, Constantinos Bougas and H. William Strauss  Characterization of the Reinjection Thallium Image

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